> Subject: Re: [PATCH v2] cpufreq: Init cpufreq only for present CPUs
>
> On Wed, Mar 12, 2025 at 05:21:27PM +0800, Jacky Bai wrote:
> > for_each_possible_cpu() is currently used to initialize cpufreq in
> > below cpufreq drivers:
> > drivers/cpufreq/cpufreq-dt.c
> > drivers/cpufreq/mediatek-cpufreq-hw.c
> > drivers/cpufreq/mediatek-cpufreq.c
> > drivers/cpufreq/qcom-cpufreq-nvmem.c
> > drivers/cpufreq/sun50i-cpufreq-nvmem.c
> >
>
> Just drop this list, totally redundant as diffstat must give that anyways.
> You have already made it stale as it doesn't match the diffstat.
>
Ok, will drop this in v3.
BR
> With that fixed:
>
> Reviewed-by: Sudeep Holla <sudeep.holla@xxxxxxx>
>
> > However, in cpu_dev_register_generic(), for_each_present_cpu() is used
> > to register CPU devices which means the CPU devices are only
> > registered for present CPUs and not all possible CPUs.
> >
> > With nosmp or maxcpus=0, only the boot CPU is present, lead to the
> > cpufreq probe failure or defer probe due to no cpu device available
> > for not present CPUs.
> >
> > Change for_each_possible_cpu() to for_each_present_cpu() in the above
> > cpufreq drivers to ensure it only registers cpufreq for CPUs that are
> > actually present.
> >
> > Fixes: b0c69e1214bc ("drivers: base: Use present CPUs in
> > GENERIC_CPU_DEVICES")
> > Signed-off-by: Jacky Bai <ping.bai@xxxxxxx>
> > ---
> > - v2 changes:
> > - Add changes for armada-8k-cpufreq, mvebu-cpfureq, qcome-cpufreq-hw,
> > scmi-cpufreq, scpi-cpufreq, virtual-cpufreq.
> > ---
> > drivers/cpufreq/armada-8k-cpufreq.c | 2 +-
> > drivers/cpufreq/cpufreq-dt.c | 2 +-
> > drivers/cpufreq/mediatek-cpufreq-hw.c | 2 +-
> > drivers/cpufreq/mediatek-cpufreq.c | 2 +-
> > drivers/cpufreq/mvebu-cpufreq.c | 2 +-
> > drivers/cpufreq/qcom-cpufreq-hw.c | 2 +-
> > drivers/cpufreq/qcom-cpufreq-nvmem.c | 8 ++++----
> > drivers/cpufreq/scmi-cpufreq.c | 2 +-
> > drivers/cpufreq/scpi-cpufreq.c | 2 +-
> > drivers/cpufreq/sun50i-cpufreq-nvmem.c | 6 +++---
> > drivers/cpufreq/virtual-cpufreq.c | 2 +-
> > 11 files changed, 16 insertions(+), 16 deletions(-)
> >
> > diff --git a/drivers/cpufreq/armada-8k-cpufreq.c
> > b/drivers/cpufreq/armada-8k-cpufreq.c
> > index 7a979db81f09..5a3545bd0d8d 100644
> > --- a/drivers/cpufreq/armada-8k-cpufreq.c
> > +++ b/drivers/cpufreq/armada-8k-cpufreq.c
> > @@ -47,7 +47,7 @@ static void __init armada_8k_get_sharing_cpus(struct
> > clk *cur_clk, {
> > int cpu;
> >
> > - for_each_possible_cpu(cpu) {
> > + for_each_present_cpu(cpu) {
> > struct device *cpu_dev;
> > struct clk *clk;
> >
> > diff --git a/drivers/cpufreq/cpufreq-dt.c
> > b/drivers/cpufreq/cpufreq-dt.c index 778916f89a51..e80dd982a3e2 100644
> > --- a/drivers/cpufreq/cpufreq-dt.c
> > +++ b/drivers/cpufreq/cpufreq-dt.c
> > @@ -283,7 +283,7 @@ static int dt_cpufreq_probe(struct platform_device
> *pdev)
> > int ret, cpu;
> >
> > /* Request resources early so we can return in case of -EPROBE_DEFER */
> > - for_each_possible_cpu(cpu) {
> > + for_each_present_cpu(cpu) {
> > ret = dt_cpufreq_early_init(&pdev->dev, cpu);
> > if (ret)
> > goto err;
> > diff --git a/drivers/cpufreq/mediatek-cpufreq-hw.c
> > b/drivers/cpufreq/mediatek-cpufreq-hw.c
> > index aa209f5527dc..74f1b4c796e4 100644
> > --- a/drivers/cpufreq/mediatek-cpufreq-hw.c
> > +++ b/drivers/cpufreq/mediatek-cpufreq-hw.c
> > @@ -303,7 +303,7 @@ static int mtk_cpufreq_hw_driver_probe(struct
> platform_device *pdev)
> > struct regulator *cpu_reg;
> >
> > /* Make sure that all CPU supplies are available before proceeding. */
> > - for_each_possible_cpu(cpu) {
> > + for_each_present_cpu(cpu) {
> > cpu_dev = get_cpu_device(cpu);
> > if (!cpu_dev)
> > return dev_err_probe(&pdev->dev, -EPROBE_DEFER, diff --git
> > a/drivers/cpufreq/mediatek-cpufreq.c
> > b/drivers/cpufreq/mediatek-cpufreq.c
> > index 2656b88db378..f3f02c4b6888 100644
> > --- a/drivers/cpufreq/mediatek-cpufreq.c
> > +++ b/drivers/cpufreq/mediatek-cpufreq.c
> > @@ -631,7 +631,7 @@ static int mtk_cpufreq_probe(struct platform_device
> *pdev)
> > return dev_err_probe(&pdev->dev, -ENODEV,
> > "failed to get mtk cpufreq platform data\n");
> >
> > - for_each_possible_cpu(cpu) {
> > + for_each_present_cpu(cpu) {
> > info = mtk_cpu_dvfs_info_lookup(cpu);
> > if (info)
> > continue;
> > diff --git a/drivers/cpufreq/mvebu-cpufreq.c
> > b/drivers/cpufreq/mvebu-cpufreq.c index 7f3cfe668f30..2aad4c04673c
> > 100644
> > --- a/drivers/cpufreq/mvebu-cpufreq.c
> > +++ b/drivers/cpufreq/mvebu-cpufreq.c
> > @@ -56,7 +56,7 @@ static int __init armada_xp_pmsu_cpufreq_init(void)
> > * it), and registers the clock notifier that will take care
> > * of doing the PMSU part of a frequency transition.
> > */
> > - for_each_possible_cpu(cpu) {
> > + for_each_present_cpu(cpu) {
> > struct device *cpu_dev;
> > struct clk *clk;
> > int ret;
> > diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c
> > b/drivers/cpufreq/qcom-cpufreq-hw.c
> > index 4b3b3dbc7d38..8422704a3b10 100644
> > --- a/drivers/cpufreq/qcom-cpufreq-hw.c
> > +++ b/drivers/cpufreq/qcom-cpufreq-hw.c
> > @@ -306,7 +306,7 @@ static void qcom_get_related_cpus(int index, struct
> cpumask *m)
> > struct of_phandle_args args;
> > int cpu, ret;
> >
> > - for_each_possible_cpu(cpu) {
> > + for_each_present_cpu(cpu) {
> > cpu_np = of_cpu_device_node_get(cpu);
> > if (!cpu_np)
> > continue;
> > diff --git a/drivers/cpufreq/qcom-cpufreq-nvmem.c
> > b/drivers/cpufreq/qcom-cpufreq-nvmem.c
> > index 3a8ed723a23e..54f8117103c8 100644
> > --- a/drivers/cpufreq/qcom-cpufreq-nvmem.c
> > +++ b/drivers/cpufreq/qcom-cpufreq-nvmem.c
> > @@ -489,7 +489,7 @@ static int qcom_cpufreq_probe(struct
> platform_device *pdev)
> > nvmem_cell_put(speedbin_nvmem);
> > }
> >
> > - for_each_possible_cpu(cpu) {
> > + for_each_present_cpu(cpu) {
> > struct dev_pm_opp_config config = {
> > .supported_hw = NULL,
> > };
> > @@ -543,7 +543,7 @@ static int qcom_cpufreq_probe(struct
> platform_device *pdev)
> > dev_err(cpu_dev, "Failed to register platform device\n");
> >
> > free_opp:
> > - for_each_possible_cpu(cpu) {
> > + for_each_present_cpu(cpu) {
> > dev_pm_domain_detach_list(drv->cpus[cpu].pd_list);
> > dev_pm_opp_clear_config(drv->cpus[cpu].opp_token);
> > }
> > @@ -557,7 +557,7 @@ static void qcom_cpufreq_remove(struct
> > platform_device *pdev)
> >
> > platform_device_unregister(cpufreq_dt_pdev);
> >
> > - for_each_possible_cpu(cpu) {
> > + for_each_present_cpu(cpu) {
> > dev_pm_domain_detach_list(drv->cpus[cpu].pd_list);
> > dev_pm_opp_clear_config(drv->cpus[cpu].opp_token);
> > }
> > @@ -568,7 +568,7 @@ static int qcom_cpufreq_suspend(struct device *dev)
> > struct qcom_cpufreq_drv *drv = dev_get_drvdata(dev);
> > unsigned int cpu;
> >
> > - for_each_possible_cpu(cpu)
> > + for_each_present_cpu(cpu)
> > qcom_cpufreq_suspend_pd_devs(drv, cpu);
> >
> > return 0;
> > diff --git a/drivers/cpufreq/scmi-cpufreq.c
> > b/drivers/cpufreq/scmi-cpufreq.c index ff2897789797..c310aeebc8f3
> > 100644
> > --- a/drivers/cpufreq/scmi-cpufreq.c
> > +++ b/drivers/cpufreq/scmi-cpufreq.c
> > @@ -104,7 +104,7 @@ scmi_get_sharing_cpus(struct device *cpu_dev, int
> domain,
> > int cpu, tdomain;
> > struct device *tcpu_dev;
> >
> > - for_each_possible_cpu(cpu) {
> > + for_each_present_cpu(cpu) {
> > if (cpu == cpu_dev->id)
> > continue;
> >
> > diff --git a/drivers/cpufreq/scpi-cpufreq.c
> > b/drivers/cpufreq/scpi-cpufreq.c index 048dc43a9997..17cda84f00df
> > 100644
> > --- a/drivers/cpufreq/scpi-cpufreq.c
> > +++ b/drivers/cpufreq/scpi-cpufreq.c
> > @@ -65,7 +65,7 @@ scpi_get_sharing_cpus(struct device *cpu_dev, struct
> cpumask *cpumask)
> > if (domain < 0)
> > return domain;
> >
> > - for_each_possible_cpu(cpu) {
> > + for_each_present_cpu(cpu) {
> > if (cpu == cpu_dev->id)
> > continue;
> >
> > diff --git a/drivers/cpufreq/sun50i-cpufreq-nvmem.c
> > b/drivers/cpufreq/sun50i-cpufreq-nvmem.c
> > index 17d6a149f580..47d6840b3489 100644
> > --- a/drivers/cpufreq/sun50i-cpufreq-nvmem.c
> > +++ b/drivers/cpufreq/sun50i-cpufreq-nvmem.c
> > @@ -262,7 +262,7 @@ static int sun50i_cpufreq_nvmem_probe(struct
> platform_device *pdev)
> > snprintf(name, sizeof(name), "speed%d", speed);
> > config.prop_name = name;
> >
> > - for_each_possible_cpu(cpu) {
> > + for_each_present_cpu(cpu) {
> > struct device *cpu_dev = get_cpu_device(cpu);
> >
> > if (!cpu_dev) {
> > @@ -288,7 +288,7 @@ static int sun50i_cpufreq_nvmem_probe(struct
> platform_device *pdev)
> > pr_err("Failed to register platform device\n");
> >
> > free_opp:
> > - for_each_possible_cpu(cpu)
> > + for_each_present_cpu(cpu)
> > dev_pm_opp_clear_config(opp_tokens[cpu]);
> > kfree(opp_tokens);
> >
> > @@ -302,7 +302,7 @@ static void sun50i_cpufreq_nvmem_remove(struct
> > platform_device *pdev)
> >
> > platform_device_unregister(cpufreq_dt_pdev);
> >
> > - for_each_possible_cpu(cpu)
> > + for_each_present_cpu(cpu)
> > dev_pm_opp_clear_config(opp_tokens[cpu]);
> >
> > kfree(opp_tokens);
> > diff --git a/drivers/cpufreq/virtual-cpufreq.c
> > b/drivers/cpufreq/virtual-cpufreq.c
> > index 45becb92aa4a..7dd1b0c263c7 100644
> > --- a/drivers/cpufreq/virtual-cpufreq.c
> > +++ b/drivers/cpufreq/virtual-cpufreq.c
> > @@ -138,7 +138,7 @@ static int virt_cpufreq_get_sharing_cpus(struct
> cpufreq_policy *policy)
> > cur_perf_domain = readl_relaxed(base + policy->cpu *
> > PER_CPU_OFFSET + REG_PERF_DOMAIN_OFFSET);
> >
> > - for_each_possible_cpu(cpu) {
> > + for_each_present_cpu(cpu) {
> > cpu_dev = get_cpu_device(cpu);
> > if (!cpu_dev)
> > continue;
> > --
> > 2.34.1
> >
>
> --
> Regards,
> Sudeep
